public TestSpriteClassState(TextureManager textureManager)
        {
            _textureManager     = textureManager;
            _testSprite.Texture = _textureManager.Get("face_alpha");
            _testSprite.SetHeight(256 * 0.5f);

            _testSprite2.Texture = _textureManager.Get("face_alpha");
            _testSprite2.SetPosition(-256, -256);
            _testSprite2.SetColor(new Color(1, 0, 0, 1));
        }
        public TestSpriteClassState(TextureManager textureManager)
        {
            _textureManager = textureManager;
            _testSprite.Texture = _textureManager.Get("face_alpha");
            _testSprite.SetHeight(256 * 0.5f);

            _testSprite2.Texture = _textureManager.Get("face_alpha");
            _testSprite2.SetPosition(-256, -256);
            _testSprite2.SetColor(new Color(1, 0, 0, 1));
        }
        public DrawSpriteState(TextureManager textureManager)
        {
            _textureManager = textureManager;
            Texture texture = _textureManager.Get("face_alpha");
            Gl.glEnable(Gl.GL_TEXTURE_2D);
            Gl.glBindTexture(Gl.GL_TEXTURE_2D, texture.Id);
            Gl.glEnable(Gl.GL_BLEND);
            Gl.glBlendFunc(Gl.GL_SRC_ALPHA, Gl.GL_ONE_MINUS_SRC_ALPHA);

        }
        public DrawSpriteState(TextureManager textureManager)
        {
            _textureManager = textureManager;
            Texture texture = _textureManager.Get("face_alpha");

            Gl.glEnable(Gl.GL_TEXTURE_2D);
            Gl.glBindTexture(Gl.GL_TEXTURE_2D, texture.Id);
            Gl.glEnable(Gl.GL_BLEND);
            Gl.glBlendFunc(Gl.GL_SRC_ALPHA, Gl.GL_ONE_MINUS_SRC_ALPHA);
        }